LOCALadk Magazine

Hemlock Black spruce -tamarack Red spruce- balsam fir Red spruce- balsam fir •••• •• -••€• €••‚• •ƒ•„ €••‚• …†•• ‡••• †• •… •„ Red spruce Black spruce- balsam fir sphagnu m Birch-beech-maple Balsam fir Canada yew Black spruce Red spruce White cedar Jack pine Tamarack Black crowberry Dwarf cranberry Creeping snowberry Alpine azalea Bog rosemary wetness, early frost wetness, thin soils thin soils, exposure infertility dominates at lower elevations, spruce from middle to high. The remaining conifers are common in one or two habitats, often extreme ones, and absent elsewhere. We often think of them as specialists, but what they may really be is ecological exiles, unable to compete in productive habitats but able to survive in marginal ones. They fall into three groups. The first, red-cedar, juniper, jack-pine, pitch pine, and red pine, are drought-tolerant species with affinity for rocks and sand. They need full sun to reproduce and either tolerate or require fire to create openings and release their seeds. The second, tamarack, black spruce, and balsam fir, can tolerate cold, nutrient-poor soils. They are common in wetlands and the alpine zone, and also, invade blow-down and burns. Their specialty is places that are too wet, acid, or infertile for other trees. The last group, white spruce, white cedar, and yew, are also tolerant of cold and wet but require mineral-rich soils or seepage. The white spruce does best in cold, fertile floodplains. The white cedar is commonest on ravine walls and rocky shores. The yew, a low shrub, hides in fertile understories and hopes the deer don't find it. The diagrams and images above, and others like them, will be part of the forthcoming Northern Forest Atlas, a series of guides to the biology and ecology of the forests of the northeastern United States and adjacent Canada. Leaf and bud charts will appear this spring, and the first full volumes in about 18 months. Twinflower Winter 2014 55

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